At over 1 million square feet of space, Porta Nuova is the largest building project in central Milan, coordinating development in three adjacent neighborhoods—Garibaldi, Varesine, and Isola—plus a new park and public spaces. To be completed in time for Expo 2015, it is also the biggest rollout of the LEED rating system in Italy.

Developed by Hines, the project includes buildings designed by Kohn Pedersen Fox, Pelli Clarke Pelli, William McDonough and Partners, and the Chicago-based firm Lucien Lagrange Architects, along with numerous Italian architects, including Stefano Boeri, who provided masterplanning for the Isola section. The mixed-use project includes residential, retail, and office spaces, cultural spaces, a new government center for the Lombardi Region, and a new city hall.

The project is a major makeover for Milan, as it makes the transition from an industrial to service-based economy, updating its image from grit to green. “With urban projects the real story about sustainability is redevelopment, building within the city rather than on the periphery,” said Mark Rylander, director at William McDonough and Partners.

For KPF and Pelli, Porta Nuova is one of a long line of collaborations with Hines, but the McDonough project, a much smaller mixed office and retail building, is the firm’s first built project for the developer. “We’ve worked on competitions for Hines, and served as a consultant,” Rylander said. “But this is a big deal for us.”

The park will be built over train lines coming in to Garibaldi station, connecting the Isola section, named for its former isolation, to the other redeveloped areas. The firm LAND is designing the park, along with Porta Nuova’s public spaces and streetscapes.

Perhaps most significantly, the project will help embed LEED standards into Italian building culture. “In many ways, these are demonstration buildings,” Rylander said.